Work vehicles, such as tractors, equipment used in farming, and construction equipment, are often operated in adverse environmental conditions. The outside temperature may be too hot or too cold for the operator's comfort and the surrounding air may be laden with dust which results from the work being done by the vehicle. It has therefore been found desirable to provide a cab for the vehicle operator, and to filter and control the temperature of the air introduced into the cab. In providing an air handling system for this purpose, it is of course desirable that the system not only efficiently condition the air, but that it be readily incorporated in the construction of the vehicle without the use of unnecessary parts or excessive labor. Accordingly, it would be advantageous to provide an air handling system for the cab of a work vehicle, which efficiently incorporates components otherwise necessary for construction of the cab. In this manner, the need for the ducts formed from additional and separate components for use in the construction of vehicle air handling systems can be reduced or eliminated.